The discovery allows for a better understanding of ancient copper production and brings to the fore new questions about when this process began.
Researchers managed to find through analyses the secrets” components from which they were made in ancient times bronze objects. They analyzed 2,300-year-old documents and coins and deciphered ancient recipes for bronze.
THE Kao Gong Ji, the earliest known technical encyclopedia, was written around 300 BC. and is part of a larger text called The Rites of Zhou. The ancient text includes six types of chemistry for mixing bronze and lists items such as swords, bells, axes, knives and mirrors, as well as how they were made.
For the past 100 years, researchers have struggled to decipher the main ingredients, referred to as “jin” “xi”. Experts believed that these words translated to copper and tin, which are key ingredients in the copper making process. When the researchers tried to recreate the recipes, however, the resulting metal did not match the composition of the ancient Chinese artifacts.
Now, two researchers believe they have pinpointed what the mystery ingredients are. The journal Antiquity published the research findings on Tuesday.
The revelation allows for a better understanding of ancient copper production and brings to the fore new questions about when this process began, given that large-scale bronze production occurred long before the six recipes in the Kao Gong Ji were written down, said study author Ruiliang Liu, curator of the Early China Collection at the British Museum in London.
In modern Chinese, jin means gold. But the ancient meaning of the word could be copper, copper alloy, or even just metal, so it was difficult to determine the specific ingredients.
“These recipes were used in the largest copper industry in Eurasia during this period,” Liu said. “Attempts to reconstruct these processes have been made for more than a hundred years, but have failed.”
Chemical analysis
Liu and the study’s co-author Mark Pollard analyzed the chemical composition of Chinese coins minted around the time the Kao Gong Ji was written. Pollard is Professor of Archeology at the University of Oxford and Director of the Research Laboratory for Archeology and Art History.
Previously, researchers believed that coins were made by diluting copper with tin and lead. The analysis showed that the chemical composition of the coins were the result of mixing two pre-prepared metal alloys, one of copper, tin and lead and the other of copper and lead.
The two researchers concluded that jin and xi were likely premixed metal alloys. “For the first time in more than 100 years, we have created an explanation of how to interpret the recipes for making bronze objects in ancient China written in the Kao Gong Ji,” Pollard said in a statement.
The findings showed that ancient Chinese copper-making relied on combining alloys rather than pure metals, and that the metallurgy was more complex than previously thought.
“It indicates an additional step – the production of precast alloys – in the process of making copper alloy objects in ancient China,” Liu said. “This represents an additional, but previously unknown feature in the history of metal production and supply in China.”
Archaeologically, this additional step would have remained unknown if not for chemical analysis, the researchers said.
“Understanding alloying practice is crucial to understanding the exceptional copper ritual vessels as well as mass production in Shang and Zhou societies,” Liu said.
Using this type of analysis could help researchers decipher other texts about ancient metallurgy from different cultures and regions in the future, the researchers said.
Read the News today and get the latest news. Follow us on Google News and be the first to learn all the news from Skai.gr.
